46 CFR §111.30-27

1. (a)Each direct current ship's service switchboard must have the equipment required by paragraphs (b) through (f) of this section.
2. (b)For each connected generator, each switchboard must have the following:
   1. (1)A circuit breaker that meets § 111.12-11 and § 111.50-5.
   2. (2)A disconnect switch or link for each generator conductor, except a switchboard having a draw-out or plug-in type generator circuit breaker that disconnects—
      1. (i)Each conductor; or
      2. (ii)If there is a switch in the generator neutral, each ungrounded conductor.
   3. (3)A field rheostat.
   4. (4)An indicator light connected between the generator and circuit breaker.
3. (c)For each two-wire generator, each switchboard must have:
   1. (1)An ammeter; and
   2. (2)A voltmeter with a selector switch that connects the voltmeter to show:
      1. (i)Generator voltage; and
      2. (ii)Bus voltage.
4. (d)For each three-wire generator, each switchboard must have the following:
   1. (1)An ammeter for:
      1. (i)The positive lead; and
      2. (ii)The negative lead.
   2. (2)A center zero type ammeter for the neutral ground connection.
   3. (3)A voltmeter with a selector switch that connects the voltmeter to show generator and bus voltage:
      1. (i)Positive to negative;
      2. (ii)Positive to neutral; and
      3. (iii)Neutral to negative.
5. (e)Each switchboard must have ground detection that meets subpart 111.05 for the:
   1. (1)Main power system;
   2. (2)Main lighting system; and
   3. (3)Emergency lighting system.
6. (f)For each shore power connection, each switchboard must have:
   1. (1)A circuit breaker or fused switch; and
   2. (2)A pilot light connected to the shore side.
7. (g)One of the voltmeters under paragraph (c)(2) or (d)(3) of this section must be connected to show:
   1. (1)For each two-wire system, shore connection voltage; and
   2. (2)For each three-wire system, shore connection voltage:
      1. (i)Positive to negative;
      2. (ii)Positive to neutral; and
      3. (iii)Neutral to negative.